21200000005 has 8 divisors (see below), whose sum is σ = 25545561624. Its totient is φ = 16889625600.

The previous prime is 21199999999. The next prime is 21200000009. The reversal of 21200000005 is 50000000212.

It can be written as a sum of positive squares in 4 ways, for example, as 1525449249 + 19674550756 = 39057^2 + 140266^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21200000005 - 2⁵ = 21199999973 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21199999937 and 21200000000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200000009) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8795476 + ... + 8797885.

It is an arithmetic number, because the mean of its divisors is an integer number (3193195203).

Almost surely, 2^21200000005 is an apocalyptic number.

It is an amenable number.

21200000005 is a deficient number, since it is larger than the sum of its proper divisors (4345561619).

21200000005 is a wasteful number, since it uses less digits than its factorization.

21200000005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17593607.

The product of its (nonzero) digits is 20, while the sum is 10.

Adding to 21200000005 its reverse (50000000212), we get a palindrome (71200000217).

The spelling of 21200000005 in words is "twenty-one billion, two hundred million, five", and thus it is an aban number.